When a constant current runs through a wire with uniform cross sectional area, the potential difference between its two points is exactly proportional to the length of the wire between the two locations.
In the electrical circuit, the potentiometer serves as a voltage divider. In radio and television (TV) receivers, the potentiometer is used for volume control, tone control, and linearity control. A potentiometer is a device that is used in medical equipment. It is used in wood processing machine.